Protractor



L. W. BUGBEE.

PROTRACTOR.

APPLICATION FILED Nov. 24, 1917.

1,408,339. Patented Feb; 28, 1922 I I smut L. W. BUGBEE nemdr a (Rb-una reoeeee.

illhl fi STA'l'ES PATENT orrice.

LUCIAN V]. B'UGEEE, 0F ENDIANAPOLIS, INDIANA, AfiSIGNOR TO AMERICAN OPTICAL COMPANY, OF (SOUTHBRLTDGE; MASSACHUSETTS, A VULUNTARY ASSOCIATION OF MfiSSAGHUSETTS. I

rso rteac'ron.

Application filed Nor-enter 2e, 191?.

To all whom may concern Be it known that l, Loom? ll". BUGBEE, a citizen or the United States, residing at Indianapolis, in the county of lllarion and State of Indiana, have invented certain new and useful Improvements in Protractors, of which the following is a specification.

This invention relates to new and useful improvements in protractors and more particularly to a device of the character which is used in securing lenses for grinding upon a block or holder in their desired position. The main object of the present invention is the provision of a protractor which is particularly adapted for bifocal lenses to facilitate the grinding of a cylindrical surface on a lens with the desired axis Another object of the presentinvention the provision of a device wherebya lens can be quickly and readily adjusted upon the grinding block and securely heldin its edjusted position duringthe grindin operation. i

lVith the above and other objects in view the invention consists in the novel-features of construction and'the combination and are rangement of parts hereinafter more fullv set forth, pointed out in the claims and shown in the accompanying drawings, in which s Figure l is a top plan view of a i tractor constructed in accordancewith my invention.

Figure 11 is side elevation of the block and carrier.

Figure Ill is a bottom plan view, parts thereof being broken away and shown in section.

Figure IV is a transverse sectional view of the block, and

Figure V is a transverse sectional view taken through the entire protr ctor.

Referring more particularlj to the drawings in which reference characters designate the several parts throughout the several views, the numeral 1 indicates a base or sup porting block provided with a centrally located recess or pocket 2 adapted to receive therein the collar or supporting ring 3 the lower edge of which is provided with an inclined surface as indicated by the numeral l.

Supported by the collar 3 is the lens block 5 having a depending; lug 6 thereon which is adapted to be disposed within the opening of the collar whereby the block will rest upon Specification of Letters Patent.

Serial No. 293,832.

the upper lace of the collar, It will be noted that the upper face of the collar is substantially flush with the upper face of the body portion so that when the block is in position the edges thereof will lie upon the upper face of the block adjacent the collar. The lower end of the lug 6 is provided with the usual pocket 7 for the reception of the operating spindle of the grinding tool wherebv the block may be readily applied to the same.

In order that the lens blocl-z may be securely held in place after the lug 6 has been arranged within the collar a set screw 8 is threaded through the side wall of the collar and engaged with the lug to retain the lens bloclr against rotation with respect to the block after the same has been set to the de sired angl The set screw 8 is operated by means or the key 9 which adapted to be inserted within the opening 10 in the end of the screw whereby the same may be readilv engaged and disengaged with the 11136. Thislrey is slidably mounted within one sidc wall of the base blocl: and is held against withdrawaltherefrom by meai s of the annular flange 11 which is movable within the opening 12 and secured to the outer end of this key is a handle member 13 whereby the hey may be readily rotated to adjust the screw 8. p

it will be understood that lens blocks oi arious size and shapes can he used in connection with my improved protractor, but they will all preferably be provided with the lug 5 whereby they may be used in connection with the collar 3. As illustrated in Figure 5the lens is secured to the upper face of he block 5 whereby the lens can be readily adjusted with respect to the collar 3 to obtain the desired axis, although it will be understood that preferred the parts may be placed in my improved positioning device while the lens holding material is still soft and the lens itself shifted on the holder to the desired position and there allowed to set. In either event my improved device serves to pro ierly position and retain the holder against slipping and to indicate the angle at which the axis of the lens is disposed with res sect to the holder.

The upper face of the base block is provided with a circumferential series or" graduations illustrated at is for the purpose of obtaining the desired axis upon Which the lens is to be ground. It will be noted that Patented Feb. 28; 1922.

Cir

the lens block can be readily rotated upon the collar 3 until the transverse and longitudinal centers are in alinernent with the desired graduations, the set screw 8 is then tightened against the lug 6 to retain the lens in its adjusted position. Secured within suitable openings within the collar are the oppositely projecting arms 15 which are adapted to engage suitable means upon the grinding machine to securely hold the block against rotation. As illustrated the inner ends of these arms 15 are held in place by means of the set screws 16 so that the arms may be readily exchanged for arms of different lengths.

From the above description taken in connection with the accompanying drawings it will be readily apparent that I have. prov'ded a protractor whereby the desired axis of a lens may be readily obtained before the grinding is carried on. It will be apparent that in adjusting the lens, the collar or ring 3 is inserted within the pocket 2 and the same turned until the arms 15 coincide with the receiving grooves 17 therefor when the set screw will be aligned with the keyway in the block. The key 9 is then inserted within the opening in the set screw to loosen the lug 6 whereby the block 5 can be rotated. After the block 5 has been adjusted so that the lens is set at the desired position, the set screw is then tightened and the device removed from the'base block and applied to the grinding tool. It will be understood that the several parts of this device may be constructed of material best suited to the purpose.

I claim:

1. A device for use in the blocking of lenses, comprising a body portion having a central recess to receive a lens block collar,

' degree graduations surrounding the. recess for laying out the axis of the lens, and a key member slidably mounted in the body portion for engagement with a locking member onthe collar to secure the lens block in de sired angularly adjusted position.

2. A benchdevice for lens grinders comlocking the lens in place.

3. A device for use in positioning a lens on a lens block having a bodyportion and laterally projecting arms, comprising a body portion having means for holding the arms in predetermined relation to the body por tion and degree graduations for indicating the position of the lens with respect to the arms in their predetermined position.

*l. A positioning device for use in connection with a cylinder lens holder, comprising a body portion having formed therein a central recess for the body of the holder and communicating grooves for the arms of the holder, whereby the holder will fitdown into said body portion, and having degree graduations formed upon its upper face'in juxtaposition to the lens receiving surface of the holder to indicate the angle of axis of the lens as respects the holder.

5. A positioning'device for use in connection with a. cylinder lens holder, comprising a body portion having formed therein acentral recess for the body of the holder and connnunicating grooves for the arms of the holder, whereby the holder will fit down into said body portion, and having degree graduationsiforrned upon its upper face in juxtaposition to the lens receiving surface of the holder to indicate the angle of axis of the lens as respects the holder, and a key member slidably and rotatablyimounted in the body portion of the'positioning device for engagement with the customary locking device on the holder.

In testimony whereof I havezafiixed my signature in presence of two witnesses.

LUGIAN W. BUGBEE.

\Vitnesses 'HARRY H. STYLL, H. K. Parsons. 

